Molten lead and/or its eutectics are leading candidates for the heat transfer medium and/or the spallation targets for next generation nuclear reactors and/or other systems using molten metal coolant. However, many of the eutectics are corrosive to many construction materials (iron based steels, for example) proposed to contain the molten material. The corrosive nature of these molten materials towards steel-based materials can be minimized by the careful control of oxygen in the molten material. Operating in the optimum range of dissolved oxygen allows a protective oxide layer to grow (and/or be maintained) on the steel-based materials, protecting the materials from corrosion by the molten material. For many oxygen control schemes, the lead first needs to be purified of its oxygen content before controlled application of oxygen back into the lead can occur. Due to the high cost of very pure lead, a lower grade of lead would be used for many large scale applications and purified in situ. Hydrogen gas can facilitate this purification process, but requires high pressure cylinders to be placed inline with and maintained in the system at all times. The time period involved for purification varies from hours to days, depending on the volume of lead to be purified. Once purified, the molten lead requires continued purification due to its interaction with the materials used to contain the molten metal, and possible contamination by oxygen egress into the system from the atmosphere. A need therefore exists for an improved apparatus and methods of purifying lead.